US613460A

US613460A - Pierre prosper monnet

Info

Publication number: US613460A
Authority: US
Publication date: 1898-11-01
Anticipated expiration: 1915-11-01

Description

UNITED STATES PATENT OFFICE.

PIERRE PROSPER MONNET, QELYONS, FRANCE, ASSIGNOR TO LA SOCIETE CHIMIQUE DES USINES DU RHGNE ANCIENNEMENT GILLIARD, P. MONNET ET CARTIER, OF SAME PLACE.

PROCESS OF MAKING AROMATIC ALDEHYD E PECIFICA'I-ION forming part ofLetters Patent No. 613,460, dated November 1, 1898'. Application filed April 29,1898. Seria1Nm67'9 1'78; m mmals.)

To all whom it may concern: have been obtained under the conditions and Be it known that I, PIERRE PROSPER MON- with the proportions stated; but the condi= NET, of Lyons, France, have invented certain tions, especially the concentration of the acid new and useful Improvements in the Producand the temperature, may be varied within 5 tion of Aromatic Aldehydes, of which the fol wide limits. lowing is a specification. Example 1: Benzaldehyde, three hundred Hitherto the conversion of methyl derivakilograms of toluol, and seven hundred kilotives of the aromatic hydrocarbons into arograms of sulfuric acid of sixty-five per cent. matic aldehydes has been ordinarily eflected are mixed together in an apparatus fitted with 10 in the following way, which may be described a stirring device, and ninety kilograms of as an indirect method: The CH of the latmanganese binoxid are slowly added in the eral chain has been converted by the action form ofafine powder during vigorous stirring. of chlorin into X--OH Ol or XOHOl and The temperature is maintained at about 40 the aldehydes have been produced from those centigrade. After all the binoxid of manga- 15 chlorination products by subsequent oxidanese has been added the stirring device is tion. Apart from the cost of chlorination kept in operation for some time in order to this process has the drawback that a certain complete the reaction. The mixture of ben amount of chlorin or chlorinated products enzaldehyde and toluol is then distilled with ters into the aromatic nucleus, and the resteam, and the separation is effected in the 20 moval of these products generally presents well-known manner. difficulties. In some cases-e.g.,in the manu- Example 2: Toluyaldehyde, (O.M.P.) The facture of benzaldehyde-this drawback is xylenes are treated as stated in Example 1 at not of much consequence, but in others-e. g., a temperature of about 25. The oxidation in the manufacture of toluylic aldehydesit takes place more readily than in the case of 25 is very appreciable. toluol.

I have discovered that aldehydes can be The process of manufacture discovered by produced by direct oxidation if care is taken me can also be applied to produce substituted that the oxidizing agent is always in the presaldehydes. For example, orthochlorbenzah ence of a large excess of the CH compound, dehyde can be easily produced by treating or 30 and this constitutes the characteristic feature thochlortoluene according to the method deof the present invention. Hitherto the direct scribed in Example 1. oxidation of the CI-I of aromatic compounds Nitro derivatives of the hydrocarbons, such has practically always yielded carboxylic as nitrotoluene and nitroxylene,also yield the acids. By this simple expedient discovered corresponding aldehydes. The behavior of 35 by me the further progress of the oxidation the hydroxyl derivatives toward oxidizing i. e., the formation of carboxylic acidcan be agents under the above conditions varies.

almost completely prevented. Thus the methyl ether of paracresol gives an The reaction which I have discovered is caaldehyde without difficulty, while the orthopable of general application. cresol compounds give no aldehyde under the 0 Up to the present I have obtained the best same conditions. results by the use of freshly-precipitated man- The sulfonic derivatives of aromatic hydroganese binoxid or Weldon mud and sulfuric carbons, their chlorids, amids, and esters, as

acid as the oxidizing agent; but according to well as the acetylated and methylated amido my experience other suitable oxidizing agents derivatives, give no aldehydes under the same 5 mayalso be employed,care being always taken conditions.

to have a large excess of the product to be oxi- What I claim, and desire to secure by Letdized at the close of the reaction. ters Patent, is-- The following examples may serve to illus- 1. The process of manufacturing aromatic trate the method of application of this new aldehydes by the direct oxidation of the 50 process of manufacture. The best yields methyl group in compounds of the aromatic roe hydrocarbon series, which process consists in treating the said compound with an oxidizing agent in the presence 6f a large excess of the said compound and separating from the unaltered material the aldehyde produced, substantially as described.

2. The process of aldehydation of the methyl group in compounds of the aromatic hydrocarbon series, which process consists in the treatment of the said compound with an oxidizing agent in such a proportion that the oxidizing agent is insufficient for the oxidation of the total methyl to aldehyde and subsequently in separating from the unaltered material the aldehyde produced.

PIERRE PROSPER MONNET.

Witnesses:

RODOLPHE PFISTER, Mimics TACI-ION.